Seal for floating roofs



May 3l, 1949. E. BOBERG SEAL FOR FLOATING HOOFS Filed NOV. 23, 1945 l irllilllllllllllifn il. llillllll-llllnlvl vlllllllllllllllt!Illllllllllill; ,llnlllllllllilt Patented May 31,1949

SEAL FOR FLOATING ROOFS Irving E. Boberg, Chicago, Ill., assignor to Chicago Bridge .& Iron Company, a corporation of Illinois Application November 23, 194.5, Serial No. 630,469 14 Claims. (Cl. 220-26) l This invention relates to a floating roof tank, and particularly to a seal for sealing the area between the edge of the roof and the shell of the tank..

Floating roof tanks are 'used for storing volatile liquids, with the roof floating on top of the 'stored liquid. This serves to reduce evaporation losses, as vthere is no large volume above the surface of the liquid. In these tanks it is' necesy 'sary that the area between the edge of the roof and the shell of the tank be sealed so as to reduce evaporation and to prevent contamination by rain water, dirt, and the like.

I have invented an improved seal for afiioating roof tank that provides a positive seal and that readily adjusts itself to varying distances between the edge of the floating roof and the shell of the tank. This improved seal comprises a shoe to be held against the shell of the tank and means for holding the shoe in vertical position. Means are also provided for sealing the top of the shoe and the shell and for sealing the floating roof and the shoe.

Theinvention will be described as related to ,Y the embodiment shown in the accompanying drawings. Of the Adrawings Fig. 1 is a fragmentary plan viewof ailoating roof tank embodying the invention, and Fig. 2 is a vertical section taken along line 2--2 of Fig. 1.

The tank shown in the accompanying drawings comprises a shell IU and a floating roof I I. Around the 'inner surface of the shell there are provided a number of flat shoes I2fplaced in endto-end relationship in order to cover substantially the entire circumference of the shell. These shoes are held opposite the periphery of the floatlng roof by means of a plurality of spaced hanger bars I 3 hingedly attached to the edge of the floating roof and to the shoe with the upper end of each bar attached to the shoe. There are also provided positioning bars I4 with each bar being hingedly attached to a hanger bar at the midpoint of the hanger bar and the positioning bar. l

'I'he top end of the positioning bar is provided with a roller I5 held against the edge of the roof by means of a bracket I6. The bracket I64 has a long arm I1 spaced from the vertical edge of the roof and substantially parallel thereto with a roller I5 held between the arm I1 and the vertical edge of the roof. The lower end of the position-,-

ing bar I4 is provided with a second roller I8 in contact with the shoe I 2. With this construction the shoe I2 is supported inl substantially vertical position at all' times, as the arrangement of hanger bars I3, positioning bars Il, rollers l5 and I8, and bracket I6 acts as a pantograph to keep the shoe I2 and the vertical edge of the floating roof always substantially parallel, no matter whatthe distance is between the shoe and the edge ofv the roof. A

There is also preferably provided a sealing means between the top of the shoe and the shell. This sealing means may have the form of a secondary seal I9 of fabric attached to the top of the shoe and held by a plurality of arms 2,0. spaced around the top edge of the floating roof. These arms are hingedly attached to the floating roof and have their upper portion 2I substantially j vertical when the iioating roof is substantially slightly less than one-half of the total length ofthe arm 20. The vertical portion 2| serves to' prevent the secondary seal assembly from moving out too far radially if the secondary seal should rise above the top of y the shell. The force of gravity is usually suicient to hold the secondary seal I9 in suliciently tight contact with the r'shell I0, but spring means or the like may be provided on the arms 20 if desired.

The top of the shoe I2 may also be provided with a flexible sealing member 22 extending from the top of the shoe to theedge of the roof. The flexible sealing member 22 and the secondary seal I9 may both be made of a fabric impregnated with a flexible impervious material. The roof edge of the sealing member 22 is fastened to the edge of the roof by any suitable fastening device, such as a plurality of spaced hooks 23 holding a bar 24' in contact with the edge of the sealing: A*

member 22. It is preferred that the top marginal portion 25 and the bottom marginal portion 26 of the shoe I2 be bent back from the vertical away from the shell I0. The secondary seal I9 and 'the sealing member 22 may be fastened to the top of the foundation, wind, and the like, often cause l the shell to get out of round. The seal as shown and described readily adjusts litself to this out-ofroundness, as is shown in dotted lines on Fig. 2.

Having described my invention `as related to a typical embodiment of the same, it is my intention that the inventionbe not limited by any o'f the details of description unl'essotherwise specified, but rather be construed broadly within its spirit and scope as set out in the accompanying claims. v q

I claim:

1. In a seal for a iloating roof tank, sealing means comprising a hanger bar hingedly attached to the edge of the floating roof and extending upwardly, a shoe hingedly carried by the upper end of said hanger bar and adapted substantially to fit against the shell of the tank. a positioning bar hingedly attached to the hanger bar a a point substantially midway between the ends of the hanger bar and the positioning bar with one end of the positioning bar contacting the side of the roof and being permissibly movable thereagainst and the other end movably contacting the shoe, means for holding said ends of the positioning bar in said contacting relationship, and a secondary seal attached to the top end of the shoe and adapted to contact the shell of the tank, said secondary seal being carried by a second hanger bar hingedly attached to the floating roof and extending upwardly toward the shell of the tank.

2. The seal of claim 1 wherein the hanger bar and the positioning bar are arranged between the vertical edge of the floating roof and the shoe and the roof end of the positioning bar is held substantially against horizontal movement while vertical.movement is permitted. i

3. The seal of claim 1 wherein at least one end of the positioning bar is provided with a roller.

4. In a seal for a floating roof tank sealing means comprising a hanger bar hingedly attached to the vertical edge of the floating roof and extending upwardly, a shoe hingedly carried by the upper end of said hanger bar and adapted substantially to t against the shell of the tank, a positioning bar of substantially the same effective length as the hanger bar hingedly attached to the hanger bar at substantially their mid-points with one end of the positioning bar contacting the vertical edge of the roof above the roof end of the hanger bar and the other end of the positioning bar contacting the shoe below the shoe end of the hanger bar, said positioning bar having both'itS ends provided with rollers, a bracket mounted on the vertical edge of the roof having an extended portion substantially parallel to vthe vertical edge of the roof with the roller on the roof end of the positioning bar held in rolling contact between said extended portion and the vertical edge of the roof, a second hanger bar hingedly attached to the top edge `toward the floating roof and the secondary seal is attached at the top marginal area.

6. The seal of claim 4 wherein the second hanger bar has its outer end substantially Vertical when the floating roof is substantially centrally positioned within the shell, with the secondary seal carried by said outer end.

7. In a seal for a floating roof tank, shoe and hanger means comprising a hanger bar hingedly attached to the edge of the floating roof and extending upwardly, a shoe hingedly carried by the upper end of said hanger bar and` adapted substantially to fit against the shell of the tank, a positioning bar hingedly attached to thehanger bar at a point substantially midway between the ends of the hanger bar and the positioning bar with one end of the positioning bar contacting p the side of the roof and being permissibly movably thereagainst and the otherend movably contacting the shoe, and means for holding said ends of the positioning bar in said contacting relationship. I

8. The seal of claim 7 wherein the hanger bar and the positioning bar are substantially equal in effective length.

9. The seal of claim 8 wherein the hanger bar and the positioning bar are arranged between the vertical edge of the iloating roof and the shoe and the roof end of the positioning bar is held substantially against horizontal movement while vertical movement is permitted.

10. The seal of claim 8 wherein at least one end of the positioning bar is provided with a. roller.

11. The seal of claim 8 wherein both ends of the positioning bar are provided with rollers and the roller on the roof end of said bar is held in rolling contact with the vertical edge of the roof by means of a bracket having an extended portion substantially parallel to the said Vertical edge with the roof roller held between said extended portion and the vertical edge of the roof.

12. In a seal for a floating roof tank, shoe and hanger means comprising a hanger bar hingedly attached to the vertical edge of the floating roof and extending upwardly, a shoe hingedly carried by the upper end of said hanger bar and adapted substantially to lt against the shell of the tank, a positioning bar of substantially the same effective length as the hanger bar hingedly attached to the hanger bar at substantially their mid-points with one end of the hanger bar contacting the vertical edge of the roof above the roof end of the hanger bar and the other end of the positioning bar contacting the shoe below the shoe end of the hanger bar, said positioning bar having both its ends provided with rollers, a bracket mounted on the vertical edge of the roof having an extended portion substantially parallel to the vertical edge of the roof with the roller on the roof end of the positioning bar held in rolling contact between said extended portion and the vertical edge of the roof.

13. In a seal for a floating roof tank, secondary sealing means comprising a shoe adapted to fit substantially against the shell of the tank, a hanger bar having its lower end hingedly attached to the top edge portion of the root and extending upwardly toward the shell of the tank, and a looped secondary seal located at the up per end of the hanger bar and secured directly thereto, said secondary seal extending downwardly therefrom in sealing relationship to the shoe, said hanger bar having its upper end portion normally substantially vertical when the floating roof is substantially centrally positioned within the shell.

14. In a seal for a oating roof tank, sealing means comprising a hanger bar hingedly attached to the edgeof the floating roof and extending upwardly, a shoe hingedly carried by the upper end of said hanger bar and adapted substantially to llt against the shell of the tank, a. positioning bar hingedly attached to the hanger bar at a point intermediate the ends of the hanger bar and the positioning bar with one end of the positioning bar contacting the side of the roof and being permissibly movable thereagainst and the other end movably contacting the shoe, a roller at each end of the positioning bar. the

5 roller on the roof end of said bar being held in rolling contact with the vertical edge of the roof by means of a bracket having an extended portion substantially parallel to said vertical edge and with the roof roller held between said extended portion and the vertical edge of the roof, and a secondary seal attached to the top end of the shoe and adapted to contact the shell of the tank, said secondary seal being carried by a second hanger bar hingedly attached to the oating roof and extending upwardly toward the shell of the tank.

IRVING E. BOBERG.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

